Process for treating tobacco

ABSTRACT

Cured leaf tobacco is treated with fatty acid esters and alcohols, and then bulked overnight in preparation for curing and subsequent cigarette manufacture. The treated product, in comparison with untreated leaf, has a higher static burning rate and its smoke is lower in total particulate matter, lower in nicotine, lower in volatile phenols, lower in benzo(a)pyrene, and lower in benzo(a)anthracene. The result is an improved, safer smoking product.

United States Patent T80 Feb. 4, 1975 [54] PROCESS FOR TREATING TOBACCO 2,953,838 9/1960 Crawford et al...-..... 131/267 X 3,039,475 1/1962 Neukomm et al... 131/140 B [75] Beltsvllle, 3,474,792 10/1969 Miller et al 131/140 B [73] Assignee: The United States of Am as 3,577,997 3/1969 B1nd1g 131/140 B represented by the Secretary of Agricuhure, Washington Primary ExaminerMelv1n D. Rem Attorney, Agent, or FirmM. Howard Silverstein; Max [22] plied: June 1974 D. Hensley; William E. Scott [21] Appl. No.: 478,417

[57] ABSTRACT [52] US. Cl- 131/17 R, 131/140 R, 131/267, Cured leaf tobacco is treated with fatty acid esters and 131/140 B alcohols, and then bulked overnight in preparation for 51 1111. C1 A24b 15/04 curing and Subsequent cigarette manufacture The 58] Field of Search 131/140, 141-144, treated Product, in comparison with untreated leaf, 13 17 2 2 7 2 9 has a higher static burning rate and its smoke is lower in total particulate matter, lower in nicotine, lower in 5 R f n Cited volatile phenols, lower in benzo(a)pyrene, and lower UNITED STATES PATENTS in benzo(a)anthracene. The result is an improved,

f k d t. 1,941,416 12/1933 Pettersson 131/140 B Sa er smo mg pm He 2,904,050 9/1959 Kiefer et al 131/269 X 7 Claims, No Drawings PROCESS FOR TREATING TOBACCO This invention relates to a process for treating cured tobacco leaf for the manufacture of a safer smoking product. More particularly, it relates to a process for treating cured, stemmed and redried leaf tobacco with chemicals to improve leaf quality and provide a safer smoking product. Tobacco differs from other agricultural products in that it is used for combustion purposes. The static burning rate reflects the easiness and completeness of combustion. Leaf material which is easier to burn usually has a lower smoke condensate per unit of the material. The levels of certain smoke products, including total particulate matter, nicotine, and total volatile phenols, are affected by the completeness of combustion.

An object of the present invention is to improve the combustion properties of cured leaf tobacco.

Another object is to prepare a tobacco product whose smoke contains a reduced amount of those components usually associated with human health problems, that is particulate matter, nicotine, volatile phenols, benzo(a)pyrenes, and bezo(a)an thra cenes.

In general, according to this invention, the above objects are accomplished by a process in which cured leaf tobacco is stemmed, redried to about 13.6 percent moisture, sprayed with an amount of fatty acid ester or alcohol or mixtures thereof adequate to make the final concentration of the ester or alcohol on the tabacco about 480 ppm and then bulked overnight to prepare it for cutting and manufacture into cigarettes or other smokable products. The fatty acid ester or alcohol or mixtures thereof are sprayed or applied to the tobacco in an aqueous mixture containing a general purpose water-soluble hydrophilic surfactant and oil-in-water emulsifier of the polyoxyethylated polyhydric alcohol ester of fatty acid type. Since the main function of the surfactant-emulsifier is to assist the treating ester or alcohol to penetrate the tobacco leaves during the bulking operation, a large number and variety of surfactantemulsifiers are operable in the process of this invention. However. because they were readily available Tween-20, a polyoxyethylene sorbitan monolaurate and Tween-80, a polyoxyethylene sorbitan monooleate, were used to exemplify this invention.

Fatty acid esters and alcohols such as CH (CH ),.COOCH and CH (CH CH OH in which n is a number from 4 to 12, and mixtures thereof, have been found to be efficacious for the purpose of this invention. Although no esters and alcohols having chain lengths shorter or longer than the above noted range were tried, they may also be usable in the process of this invention. The ratio of ester to surfactantemulsifier in the aqueous mixture was usually about 3 to 4 parts of ester to 1 part of surfactant-emulsifier, while the ratio of alcohols to surfactant-emulsifier was usually about 5 to 3. However, these ratios are not critical and can be varied with little or no effect on the results.

The process of this invention is applicable to the treatment of any type of, cured tobacco leaf such as flue-cured and air-cured tobacco. In addition, it is also applicable to ground tobacco leaf material such as tobacco that is being readied for manufacture into reconstitutued sheets. The only stipulation is that the leaf material be treated prior to being made into the final product.

The invention is illustrated by the following examples.

EXAMPLE 1 Cured bright type leaf tobacco was stemmed, blended, and redried to 13.6 percent moisture. A formulation containing about 4 parts of methyl caprate and 1 part ofa surfactant, Tween-20, and weighing 192 g was made to four gallons with water, and sprayed onto 662 pounds of tobacco. The treated tobacco was then bulked overnight before cutting for cigarette manufacture. The final concentration of the methyl caprate in treated tobacco was 480 ppm.

EXAMPLE 2 Cured bright leaf tobacco was stemmed and redried to 13.6% moisture. A'formulation containing about 5 parts of a mixture of equal parts of l-octanol and 1- decanol and about 3 parts of a surfactant, Tween-80, was made tofour gallons with water, and sprayed onto 662 pounds of tobacco. The treated tobacco was bulked overnight before cutting for cigarette manufacture. The final concentration of the mixed alcohol in tobacco was 480 ppm.

EXAMPLE 3 Cured bright leaf tobacco was stemmed, redried to 13.6 percent moisture content. Four gallons of water were sprayed onto 662 pounds of tobacco which was then bulked overnight before cutting for cigarette manufacture.

Cigarette samples from Examples 1, 2, and 3 were smoked under controlled laboratory conditions. The static burning rate, amount of wet and dry total particulate matter (TPM), nicotine in smoke, total volatile phenols, benzo(a)pyrene (BaP), and benzo(a)anthracene (BaA), were determined. A comparison of the smoke delivery and selected smoke components, from cigarettes made of treated and untreated leaf tobacco is shown in Table 1. It is evident that leaf tobacco treated with methyl caprate as in Example 1 and treated with a mixture of fatty alcohols as in Example 2, in comparison with the nontreated control in Example 3, had increased the static burning rate and decreased wet TPM, dry TPM, nicotine, TPM minus nicotine (FTC tar), total volatile phenols, BaP, and BaA. In general, the results show a significant decrease in the cigarette smoke of those components that are generally associated with human health problems.

Bioassay procedures have shown that the process of this invention does not impart any carcinogenic properties to the product. The cigarette smoke condensate of the products of each of the above examples was tested for carcinogenicity by a mouse skin painting technique. As seen in Table 11, there was no significant difference between the results obtained from the products of Examples 1 and 2 and the results obtained by the control. Example 3.

TABLE 1 Comparison of Smoke Delivery and Smoke Components from Cigarettes Made of Treated and Untreated Tobacco Leaf Treated with mixture of Treated with l-octanol and Untreated methyl caprate l-decanol Control (Example 1) (Example 2) (Example 3) Static Burning Rate mg/min. 46.4 47.4 39.3 Difference in +l8.l +20.6 Wet TPM mg/cig.* 36.3 40.1 44.l Difference in l7.7 -9.l Dry TPM mglcig. 32.4 36.0 40.1 Difference in 72 l9.2 l0.2 Nicotine mg/cig. 3.12 3.32 3.80 Difference in -l7.9 l2.6 TPM minus Nicotine mg/cig. 29.3 32.7 40.8 Difference in 7: 28.2 -l9.9 Total volatile phenols ug/cig. 220.0 195.0 248.0 Difference in l 1.7 21.3 Benzo(a)pyrene a)ug/l g tob. smoked 4.19 4.71 5.36 Difference in 71. 24.l l2.l b)ug/cig.* 35.0 39.5 43.5

Difference in Z: l9.5 9.2 Benzo(a)anthracene a)ug/l00 g tob. smoked 6.24 6.97 7.7] Difference in 19.1 9.6 b)ug/cig." 52.2 58.9 62.6

Difference in -l6.6 5.9

All cigarettes are calculated as I00 mg weight.

TABLE [I Bioassay Results of Mouse Skin Painting of Cigarette Smoke Condensates from Products of Examples 1, 2, and 3 I claim:

1. A process for improving the combustion properties of cured leaf tobacco and for decreasing the amount of components associated with human health problems in the smoke of cured leaf tobacco comprising treating said cured leaf tobacco by applying to the tobacco a substance selected from the group consisting of CH (CH ),,COOCH;, in which n is a number from 4 to 12, CH (CH ),,CH OH in which n is a number from 4 to 12, and mixtures thereof, said substance being applied in an aqueous mixture containing a combination emulsifier and surface active agent and then bulking the treated leaf tobacco.

2. The process of claim 1 in which the final concentration of the substance on the treated tobacco is about 480 ppm.

3. The process of claim 2 in which the substance is methyl caprate.

4. The process of claim 2 in which the substance is a mixture of from 40 to 50 percent l-octanol and from 60 to 50 percent l-decanol.

5. A process for improving the combustion properties of cured leaf tobacco and for decreasing, in the smoke of said tobacco, the amounts of particular matter, nicotine, volatile phenols, benzo(a)pyrene, and benzo(a)anthracene comprising treating said cured leaf tobacco by applying to the tobacco a substance selected from the group consisting of methyl caprate and a mixture of from 40 to 50 percent l-octanol and from 60 to 50 percent l-decanol, said substance being applied in I an aqueous mixture containing a combination emulsitier and surface active agent, and then bulking the treated leaf tobacco.

6. The process of claim 5 in which the final concentration of the substance on the treated tobacco is about 480 ppm.

7. A smoking tobacco product which has been improved by increasing its static burning rate and by decreasing, in the smoke of said product, the amounts of particulate matter, nicotine, volatile phenols, benzo(a)pyrene and benzo(a)anthracene, said improved product having been prepared by applying to cured leaf tobacco a substance selected from the group consisting of methyl caprate and a mixture of from 40 to 50 percent l-octanol and from 60 to 50 percent l-decanol and then bulking the so-treated leaf tobacco.

UNETED STATES ATENT (FENCE crmcmih er EQTIN Patent No. 3986396145 Dated l' *9 1975 Tier: Cn Tee Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In Column 1 in the feetnote to Table I "that portinn reading "1W3" sheuld. read M 1800 a Signed and sealed this 15th day of July 1975.

(SEAL) Att'GSiI:

CD MARSHALL DANN RUTH C. MASON Cemnissiener of Patents Arresting Officer and Trademarks 

2. The process of claim 1 in which the final concentration of the substance on the treated tobacco is about 480 ppm.
 3. The process of claim 2 in which the substance is methyl caprate.
 4. The process of claim 2 in which the substance is a mixture of from 40 to 50 percent 1-octanol and from 60 to 50 percent 1-decanol.
 5. A process for improving the combustion properties of cured leaf tobacco and for decreasing, in the smoke of said tobacco, the amounts of particular matter, nicotine, volatile phenols, benzo(a)pyrene, and benzo(a)anthracene comprising treating said cured leaf tobacco by applying to the tobacco a substance selected from the group consisting of methyl caprate and a mixture of from 40 to 50 percent 1-octanol and from 60 to 50 percent 1-decanol, said substance being applied in an aqueous mixture containing a combination emulsifier and surface active agent, and then bulking the treated leaf tobacco.
 6. The process of claim 5 in which the final concentration of the substance on the treated tobacco is about 480 ppm.
 7. A smoking tobacco product which has been improved by increasing its static burning rate and by decreasing, in the smoke of said product, the amounts of particulate matter, nicotine, volatile phenols, benzo(a)pyrene and benzo(a)anthracene, said improved product having been prepared by applying to cured leaf tobacco a substance selected from the group consisting of methyl caprate and a mixture of from 40 to 50 percent 1-octanol and from 60 to 50 percent 1-decanol and then bulking the so-treated leaf tobacco. 